Conclusion

Simply stated, MSI's GeForce GTX 1080 Ti Lightning Z is top-notch in every way. It's just too bad that the card is perpetually out of stock. Newegg says it may never be back. B&H calls it discontinued. Amazon Marketplace vendors are asking as much as $1400 for the remaining supply. Let's just call this a piece of exhibition hardware for now, then.

Under air cooling, it's a high-performance flagship with an aggressive factory overclock and a massive heat sink. The unusual PCB is made of high-quality materials. Only one or two other models out there can measure up to its design.

Although the Lightning Z has some overclocking headroom at ambient temperatures, you really need liquid nitrogen to unlock its true potential. After tens of hours under LN2 (not to mention the 200+ liters we burned through), none of our four samples showed even the slightest sign of weakness. In the event that you're able to get your hands on Afterburner Extreme, the only thing holding you back will be talent.

Vanilla 1080ti’s get to 2050mhz under air, and 2050-2100mhz under water. I’ve read reviews of lots of top of the line 1080ti’s and have yet to see any cards improve on stock performance. Unless the acoustics of the cooling solution are superior there is absolutely no benefit to any of these high end cards. GP102 is the undisputed king of GPU’s, but it doesn’t appear to benefit at all from enhanced power delivery systems. Not worth spending any money on them.

I wonder if anyone has tried a closed loop LN2 circuit. Would keep it from changing state from liquid to gas. Downside being it would take a butt-ton of equipment.

Wouldn't work. Liquid nitrogen is only cold when it is allowed to evaporate. In a closed loop it actually wouldn't be cold anymore at all - it would simply be at room temperature but with 2200 psi of pressure. Water is far more effective at transferring heat than liquefied (under pressure) nitrogen gas.

Condensing room temperature nitrogen gas to liquid would be an exothermic phase change. (This is what you pay for when buying LN2. Nitrogen gas itself is quite literally all around you, although with some "impurities" like oxygen.)

Pouring your liquid LN2 into an area with standard atmospheric pressure allows the liquid to evaporate and expand.

The ideal gas law states that when a gas expands it also becomes cooler.

On the opposing side when a gas is compressed it becomes hotter.
(This heat is what supplies our sun with the temperatures necessary for nuclear fusion.)